There are a number of technological systems available for arranging meeting between participants located in different areas. These systems may include audio visual multipoint conferences or videoconferencing, web conferencing and audio conferencing.
The most realistic substitute of real meetings is high-end videoconferencing systems. Conventional videoconferencing systems comprise a number of end-points communicating real-time video, audio and/or data streams over and between various networks such as WAN, LAN and circuit switched networks. The end-points include one or more monitor(s), camera(s), microphone(s) and/or data capture device(s) and a codec. Said codec encodes and decodes outgoing and incoming streams, respectively.
Traditional Audio Visual Multipoint conferences have a central Multipoint Control Unit (MCU) with three or more endpoints connected. These MCU's perform switching functions to allow the audiovisual terminals to intercommunicate in a conference. The central function of an MCU is to link multiple video teleconferencing sites (EP-endpoints) together by receiving frames of digital signals from audiovisual terminals (EP), processing the received signals, and retransmitting the processed signals to appropriate audiovisual terminals (EP) as frames of digital signals. The digital signals may include audio, video, data and control information. Video signals from two or more audiovisual terminals (EP) can be spatially mixed to form a composite video signal for viewing by teleconference participants. One example of mixing and transcoding is converting four QCIF video streams into one CIF video stream.
When the different video streams have been mixed together into one single video stream the composed video stream is transmitted to the different parties of the video conference, where each transmitted video stream preferably follows a set scheme indicating who will receive what video stream. In general, the different users prefer to receive different video streams. This result in that the multi point control unit needs to perform a large amount, of video mixing, which in turn results in a large demand for processing power.
In order to form such a composed video stream, the conventional solution is to decode the separate incoming video streams from the respective parties, mix the video streams in accordance with the set schemes for the different users and then encode the composite images and transmit it to the respective users from the MCU. Thus, MCU's are provided with a set of encoders and decoders. One decoder is required for each incoming coded bit stream, whereas encoders usually can be shared among several outgoing bit streams. Hence, the required encoder resources in an MCU are usually less than the required decoder resources.
This requires a certain amount of processing power and inputs/outputs assigned to each conference, making the MCU unavailable for new conferences when ongoing conferences already occupies the resources in the MCU.
To provide multipart conferences without MCU, some video endpoints do have integrated MCU features. These are typically meeting room applications, and more expensive conferencing systems. There are also a set of conferencing bridges that enables video multi point conferencing. Both these solutions (Meeting Rooms, Conferencing Bridges) do require conference setup actions, prior to every meeting. This is typically to book a room, schedule the meeting in an administration interface, distribute information, notifying the conference number etc), which typically is done through a user interface of a Management System. This may make the process of hosting a multipoint conferencing event a time consuming task, and the threshold for using this technology to high.
In an environment where personal endpoints are widespread, the usual configuration is small video systems, incapable of hosting a multipoint conference. This does not mean that the need for multipoint visual conferencing is absent. According to prior art, is it not possible to utilize the personal single call video endpoints for multipoint video conferencing, without doing extra management and time consuming preparations.